Why is he good?
Look at the link in comment 9. Many freepers have posted why they are of the opinion that he'd be a good choice.
Why is he bad?
Because he is very intelligent, knows how to bust balls when necessary, and did great work in his role in Afghanistan.
His short biography:
Dr. Zalmay Khalilzad was nominated Ambassador Extraordinary and Plenipotentiary of the United States of America to Iraq by President Bush on April 5, 2005. Dr. Khalilzad was sworn in on Tuesday, June 21, 2005 in Baghdad and presented his credentials to President Talabani the same day.
Dr. Khalilzad served as Ambassador to Afghanistan from November 2003 to June 2005, during which time he continued as the Special Presidential Envoy to Afghanistan. For his service in Afghanistan Secretary Rumsfeld awarded Dr. Khalilzad the Defense Department medal for outstanding public service. President Karzai awarded him the King Ghazi Ammanullah Medal, Afghanistan’s highest medal. Earlier he served as Special Assistant to the President and Senior Director for Islamic Outreach and Southwest Asia Initiatives at the National Security Council. Prior to that, Dr. Khalilzad was Special Assistant to the President and Senior Director for Southwest Asia, Near East, and North African Affairs at the National Security Council. He was also a Special Presidential Envoy and Ambassador at Large for the Free Iraqis. Dr. Khalilzad headed the Bush-Cheney transition team for the Department of Defense and has been a Counselor to Secretary of Defense Rumsfeld.
Between 1993 and 1999, Dr. Khalilzad was Director of the Strategy, Doctrine and Force Structure program for RAND's Project Air Force. While with RAND, he founded the Center for Middle Eastern Studies. Between 1991 and 1992, Dr. Khalilzad served as Assistant Deputy Under Secretary of Defense for Policy Planning. Secretary Cheney awarded Dr. Khalilzad the Department of Defense medal for outstanding public service. He also served as a senior political scientist at RAND and an associate professor at the University of California at San Diego in 1989 and 1991. From 1985 to 1989 at the Department of State, Dr. Khalilzad served as Special Advisor to the Under Secretary of State for Political Affairs working policy issues, advising on the Iran-Iraq war and the Soviet War in Afghanistan. From 1979 to 1986, Dr. Khalilzad was an Assistant Professor of Political Science at Columbia University.
Dr. Khalilzad received his bachelor's and master's degree from the American University of Beirut, Lebanon. He went on to earn a Ph.D. from the University of Chicago. Dr. Khalilzad is the author of more than 200 books, articles, studies and reports. His work has been translated in many languages including Arabic, Chinese, German, Japanese and Turkish. He is married and has two sons